Please Help! Temperature profile UDF for 3D geometry
 

Hi all,
I am using UDF to define temperature field in 2D fluid flow problem. If I would like to put 3D temperature profile , what modification of UDF for 2D temperature profile is required.

My UDF for 2D temperature profile is :

DEFINE_PROFILE(inlet_temp, thread, index)
{
real x[ND_ND];
real temp, y;
face_t f;

begin_f_loop(f, thread)
{
F_CENTROID(x,f,thread);
y = x[1];
temp = (12285-333)*(1-(pow((y/0.0035),4)))+(333);
F_PROFILE(f, thread, index) = temp;
printf("Temperature calculated by UDF is %f\n",temp);
}
end_f_loop(f, thread)
}

what would be for 3D?

Thanks in advance.